The present invention refers to a control gear for a dynamo connected to a hub, particularly a wheel hub and which dynamo is of the type which incorporates a stator and a armature rotatable with the hub, and being arranged radially relative to each other and where the stator or armature can be prevented from rotation by means of a locking device, and where a current collector is arranged to lead off current generated during arresting of stator or armature.
Such a hub-connected dynamo is a suitable design for the current supply of the lighting of a bicycle, even if its use is not limited thereto.
Dynamos of this type, which are used for generation of current for bicycle lighting have been on the market in a plurality of different embodiments and they entail advantages such as reliability, high efficiency, slight influences from weather conditions and the state of the roads, no tire wear and easier prevention of thefts than most conventional arrangements.
In Finnish patent specification No. 40443 is described such a bicycle dynamo incorporating an annular stator body with a stator winding, which is connected to the hub of the bicycle wheel and always participates in the rotation of the bicycle wheel, and a rotatably supported rotor, arranged inside the stator body and arrestable against rotation by means of a control latch, which extends through a covering plate and can be make to assume a current generating position in which the rotor is thus prevented from rotation and which is free to rotate in the second, current free position. Current collectors are arranged in the covering lid.
The problem of this design is that it is rather difficult to operate the dynamo and particularly to disconnect it, which means that the dynamo can cause accidents if during bicycling the bicycle lights need to be turned ON or OFF, as it is thereby necessary to kick with a foot against the control latch which projects from the hub.